Multicolor light source

ABSTRACT

A multicolor light source employs translucent enclosures about multiple filaments with each enclosure having unobstructed exposure to a wide angle translucent portion of an envelope.

United States Patent 1 Ackley [451 May 6,1975

54] MULTICOLOR LIGHT SOURCE [76] Inventor: Donald M. Ackley, 1115 17th St.,

Hermosa Beach, Calif. 90254 [22] Filed: Mar. 28, 1973 [21] Appl. No.: 345,765

[52] US. Cl. 315/68; 315/74; 313/115 [51] Int. Cl.....H0lj 19/78; H01j61/40;H01k H26 [58] Field of Search......... 315/69, 68, 74, 317, 154,

[56] References Cited UNITED STATES PATENTS 1,649,975 11/1927 Parks 313/220 X 1,688,549 Llaurado 313/112 2,150,232 3/1939 Major 315/69 X 2,209,187 7/1940 Briefer et al...,....... 313/316 X 2,573,775 ll/195l Schwenger 313/273 X 3,023,667 3/1962 Lessman 313/115 X 3,225,243 12/1965 Dauser 313/112 Primary Examiner-Nathan Kaufman Attorney, Agent, or FirmWilliam W. l-laefliger [57] ABSTRACT A multicolor light source employs translucent enclosures about multiple filaments with each enclosure having unobstructed exposure to a wide angle translucent portion of an envelope.

9 Claims, 5 Drawing Figures MULTICOLOR LIGHT SOURCE BACKGROUND OF THE INVENTION This invention relates generally to light sources, and more particularly concerns the provision of a source whose light output may be controllably varied in color.

Prior light sources have either lacked capability for color variation, or else lacked the unusually advantageous combinations of construction, mode of operation and results as now afforded by the present invention. Among these are capability for simultaneous illuminations of the same substantial portion of a translucent envelope by multiple color sources to enable most efficient mixing of the light to produce the desired color; masking of unwanted light transmission to the exterior from light filtering cylindrical enclosures for multiple filaments, masking of direct path transmission of light between the enclosures; simplicity of construction, and high efficiency of variably colored light transmission from the source.

SUMMARY OF THE INVENTION It is a major object of the invention to provide a controllably variable colored light source overcoming the deficiencies of prior sources and having multiple advantages as referred to. Basically, the source comprises an envelope or bulb having a light passing or translucent portion; at least two (and preferably three) filaments located within the envelope interior so that the light passing portion of the envelope subtends a substantial angle the apex of which is proximate the filaments; a glass enclosure about each filament and characterized in that light of different colors emanates from the respective enclosures when the filaments therein are electrically energized to incandescence; and each enclosure having direct and unobstructed exposure to the light passing or translucent portion of the envelope. As will be seen, the light passing portion of the envelope subtends angles of at least 90 and whose apices are located at the respective enclosures.

Further, the enclosures may be generally cylindrical and arranged in parallel side-by-side relation; blocking means may be provided to block escape to the exterior of unfiltered light emanating endwise from the enclosures and also to block direct path travel between the enclosures of filtered light; electrical circuit means may be provided to control relative energization of the filaments; and the latter may be supported by arms extending to opposite ends of the cylindrical enclosures to also support the latter, as will be seen.

These and other objects and advantages of the invention, as well as the details of an illustrative embodiment, will be more fully understood from the following description and drawings, in which:

DRAWING DESCRIPTION FIG. 1 is a vertical elevation showing one preferred form of the colored light source.

FIG. 2 is an enlarged vertical elevation showing details of the filament and enclosure assembly of FIG. 1;

FIG. 3 is an enlarged vertical section showing filament and glass enclosure and support;

FIG. 4 is a schematic showing of filament and glass enclosure exposure to a light passing or translucent portion of the envelope; and

FIG. 5 is a circuit diagram.

DETAILED DESCRIPTION In the drawings, the illustrated colored light source 10 includes an envelope 11 having a light passing or translucent portion 11a. The envelope may advantageously comprise a Pyrex type glass and the light passing portion is formed to subtend a substantial solid angle A the apex of which is located proximate a filament and glass enclosure assembly generally designated at 12. Angle A is typically greater than and preferably near about The assembly 12 includes at least two filaments, (preferably three, designated at l4, l5 and 16) located within the typically evacuated interior 13 of the envelope. Glass enclosures 1719 extend at least part way about the filaments, and are characterized in that light of different colors emanates or is transmitted from the respective enclosures when the filaments are electrically energized to incandescence. Further, each enclosure has direct and unobstructed exposure to the light passing or translucent portion 11a of the envelope. Thus, for example, envelope portion 11a typically subtends solid angles B, C and D of at least 90 and whose apices are located at the respective enclosures as is clear from FIG. 4. The translucent portion 11a of the bulb desirably subtends each of the angles B, C, and D.

More specifically, each enclosure may be generally cylindrical and may consist of a Pyrex type glass treated to act as a filter, of a different color for example, so that red light is transmitted by enclosure 17, yellow light by enclosure 18 and blue light by enclosure 19, or other combinations. For example, the glass may be suitably colored when formed, or dyed thereafter, as is known. Further, the glass enclosures extend in generally parallel, side-by-side relation, there being a light mask or masks extending between successive enclosures. For the latter purpose, a U-shaped metallic mask may have elongated arms 20 and 21 respectively projecting between cylindrical enclosures 17 and 18, and between enclosures 18 and 19, to block light transmission directly between the enclosures or filters so as to remove interference effects. The mask may be carried by the insulative support 22 carrying the enclosures and filaments, and which may also consist of glass.

FIG. 3 shows the glass support 22 carrying conductive metal arms 23 which extend to opposite ends of a typical enclosure 18. Opposite end wires 15a of the filament 15 are attached to bowed portions 23a of the arms 23 so as to transmit flow of current therebetween, the arm bowed portions also supporting the enclosure 18 as by partial reception into the open ends thereof, as shown. FIG. 1 shows one form of light bulb incorporating the invention, and having a plug-in socket base 24 (which may alternately take a form to accommodate a screw-in or bayonet type socket). The socket base carries the insulative support 22, and electrical terminals 25-28 protrude from the lower end of the socket base. Terminal 28 is a common terminal for all filaments, as is clear from the FIG. 5 wiring diagram. One of the arms 23 for each filament is connected with one of the terminals 25-27, and the other arm is connected with the common terminal 28, as is clear from FIG. 2.

Referring back to FIG. 1, light masking means is provided to extend in alignment with opposite ends of cylindrical enclosures so as to block escape through the envelope of light traveling axially endwise from the cylindrical enclosures. In the example, the masking means takes the form of an opaque region on the envelope, as for example the coated or silvered region 29 below the level indicated by line 30. Accordingly, light escaping from the open ends of the cylinders is blocked from escape through the envelope and so does not interfere with the desired color light transmission from the light passing hemisphere portion 11a. All light transmitted by the latter has the characteristic color selected as by controlled energization of the filaments. The illustrated outer configuration or shape of the bulb is not to be considered limited to that shown. As an example, the configuration could resemble a floodlight. With reference to such control, FIG. shows the filamerits connected in parallel with a current source 32, as via a control unit 33. The latter may for example contain variable resistors 35, 36 and 37, connected in series with the respective filaments 14, 15 and 16, whereby desired color output may be achieved by relative variation of the resistors. The latter may take the form of potentionmeters and their controls may be gang-connected so that a single control operates all the resistors. Such control may be effected manually, or

automatically as by a computer represented by box 33. Solid state devices, such as transistors may be used for control.

The use of various colors, such as red, yellow and blue filters at 17, 18 and 19, together with the described controls, enables variation of the color output through the complete spectrum. Thus, the mixing of the light from the filters, with intensity control as effected by the variable resistors, achieves the desired effeet.

I claim:

1. In a colored light source, the combination comprising a. an envelope having a translucent portion,

b. at least two filaments located within the interior of the envelope so that said translucent portion subtends a substantial angle the apex of which is proximate the filaments,

c. a light transmitting glass enclosure extending at least part way about each filament and characterized in that light of different colors is transmitted through the respective enclosures when the associated filaments are electrically energized to incand. each enclosure having a generally cylindrically curved surface with direct and unobstructed exposure to said translucent portion of the envelope,

e. first light masking means in alignment with opposite ends of the enclosures to block escape through the envelope of light traveling axially endwise from said enclosures, and f. second light masking means extending between the enclosures to block light transmission directly therebetween, thereby to prevent interference effects.

2. The combination of claim 1 wherein said translucent portion of the envelope subtends angles of at least and whose apices are located at the respective enclosures, said first light masking means defined by an opaque region of the envelope annularly surrounding said enclosures and defining a circular edge at a level substantially equally spaced above each enclosure.

3. The combination of claim 1 wherein each glass enclosure is generally cylindrical.

4. The combination of claim 1 wherein the enclosures consist of light filtering Pyrex type glass.

5. The combination of claim 3 wherein said first masking means comprises an opaque region on the envelope.

6. The combination of claim 1 wherein the glass enclosures are generally cylindrical and extend in generally parallel side-by-side relation.

7. The combination of claim 6 wherein there are three of said enclosures characterized in that light transmitted from the respective enclosures is red, yellow and blue.

8. The combination of claim 7 including electrical circuit means connecting with the filaments to selectively electrically energize the filaments associated with said enclosures.

9. The combination of claim 1 wherein the glass enclosures are generally cylindrical and are carried by support arms extending to opposite ends of the enclosures, the filaments attached to the support arms to transmit flow of electrical circuit, therebetween. 

1. In a colored light source, the combination comprising a. an envelope having a translucent portion, b. at least two filaments located within the interior of the envelope so that said translucent portion subtends a substantial angle the apex of which is proximate the filaments, c. a light transmitting glass enclosure extending at least part way about each filament and characterized in that light of different colors is transmitted through the respective enclosures when the associated filaments are electrically energized to incandescence, said enclosures contained within the envelope, d. each enclosure having a generally cylindrically curved surface with direct and unobstructed exposure to said translucent portion of the envelope, e. first light masking means in alignment with opposite ends of the enclosures to block escape through the envelope of light traveling axially endwise from said enclosures, and f. second light masking means extending between the enclosures to block light transmission directly therebetween, thereby to prevent interference effects.
 2. The combination of claim 1 wherein said translucent portion of the envelope subtends angles of at least 90* and whose apices are located at the respective enclosures, said first light masking means defined by an opaque region of the envelope annularly surrounding said enclosures and defining a circular edge at a level substantially equally spaced above each enclosure.
 3. The combination of claim 1 wherein each glass enclosure is generally cylindrical.
 4. The combination of claim 1 wherein the enclosures consist of light filtering Pyrex type glass.
 5. The combination of claim 3 wherein said first masking means comprises an opaque region on the envelope.
 6. The combination of claim 1 wherein the glass enclosures are generally cylindrical and extend in generally parallel side-by-side relation.
 7. The combination of claim 6 wherein there are three of said enclosures characterized in that light transmitted from the respective enclosures is red, yellow and blue.
 8. The combination of claim 7 including electrical circuit means connecting with the filaments to selectively electrically energize the filaments associated with said enclosures.
 9. The combination of claim 1 wherein the glass enclosures are generally cylindrical and are carried by support arms extending to opposite ends of the enclosures, the filaments attached to the support arms to transmit flow of electrical circuit, therebetween. 